Chapter 7: Adaptations to Environment Flashcards
Large diversity of species and of adaptations to ?
different environmental conditions
All species must acquire what to be fit?
- energy and matter to survive, grow and reproduce (to be fit)
AMWR for fitness?
- Acquisition and digestion of food (organisms put a lot of energy into acquiring and digesting food)
- Maintenance of body temperature
- Water balance
- Response to cycles of light and temperature
- 1 Size as a constraint on Evolution:
- Organisms range in?
size
- 1 Size as a constraint on Evolution:
- morphological and physiological features ____ with body size.
chane
- 1 Size as a constraint on Evolution:
- Surface area to volume ratio?
- smaller organisms have larger surface area relative to volume….
L> ratio = how much area is exposed to the environment vs volume of their body
Surface Area to Volume Ratio:
- Transfer needed between ___ and ____.
-environment and interior of organism Ex: oxygen
Surface Area to Volume Ratio:
- Diffusion is effective for what sized animals?
- small
Surface Area to Volume Ratio:
- Large organisms how do they get oxygen to their interior?
- active transport via lungs, circulatory system
Surface Area to Volume Ratio:
- Body size constraints also apply to other?
metabolic processes
Acquisition and Digestion of Food:
- variety of methods to acquire and digest foods such as?
- herbivory
- carnivory
- omnivory
Acquisition and Digestion of Food:
- each feeding group has characteristic adaptations. Such as?
ex: ruminants(mammals that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion, principally through bacterial actions. ) like deer and cows are adapted to digest cellulose
* *omnivores do not digest cellulose well
Nutrition and Oxygen:
- need ____ and ___.
- mineral elements and amino acids
Nutrition and Oxygen:
- Release of energy from food mostly through____.
- aerobic respiration
Nutrition and Oxygen:
- need???
oxygen
Why is this more of a problem for aquatic organisms?
it goes via passive transport
- if the current was in the same direction you wouldn’t acquire as much oxygen
- *counter current
Regulation of Internal Conditions:
- Organisms must regulate their internal environment despite what?
- changes n the external environment aka HOMEOSTASIS
Regulation of Internal Conditions:
- Homeostasis?
the property of a system in which variables are regulated so that internal conditions remain stable and relatively constant.
Regulation of Internal Conditions:
-Regulated an internal system by homeostasis involves a ?
negative feedback …= the means to which a system returns back to a set point within the system
Regulation of Internal Conditions:
-Homeostatic plateau?
- max and min range (middle is where we want to be)
Regulation of Internal Conditions:
- organisms have a defined range for where they can?
function at
Regulation of Internal Conditions:
- Control of homeostasis is both ___ and ____
physiological and behavioural
Regulation of Internal Conditions:
- homeostasis is effective over a certain range of? (ex)
temperature
Regulation of Internal Conditions:
- What are some behavioural things you do to regulate temperature ?
- metabolism is ramped up
- eat
- drink warm drinks
- shiver
- when we are hot we move water to the outside via sweating
Energy transfer among objects? (3)
- Conduction - energy transfers throughout the body…
- Convection -gaining heat from the environment
- Radiation - gain heat from environment
L> animals typically generate more metabolic heat than plants do …mobility provides a mode for us to keep within our desired range
**bounce the radiation back i.e. losing heat
Energy Exchange within Environment :
-Animals are often isolated from the surrounding environment via?
boundary layer
Energy Exchange within Environment :
- layers of insulation change the body’s?
- conductivity
* *temperature differential been the outside and indie
Types of Temperature Regulation?
- Homeotherms
- Poikiloththerms
- heterotherms
Types of Temperature Regulation:
-Homeotherms ??
maintain constant internal temperatures independent of external temperatures by endothermy (internal heat production…..physiological generation and regulation of body temperature by metabolic means : the property or state of being warm-blooded)
Types of Temperature Regulation:
-Poikilotherms??
- maintain body temperature through external sources: ectothermy (An organism that regulates its body temperature largely by exchanging heat with its surroundings; a poikilotherm)
- *ex: snakes..absorbing heat…their body temp is the same as the environment
Types of Temperature Regulation:
- Heterotherms?
- use both endothermy and ectothermy depending on conditions
Ex: bears going into hibernation
Poikilotherms are affected by environment:
Environmental temperatures control the rates of?(2)
- metabolism and activity
Poikilotherms are affected by environment:
- they gain and lose ___ easily from environment
heat
Poikilotherms are affected by environment:
- explain the graph
y= body temperature (C)
x= ambient temperature
- linear! both are increasing together and would decrease together
Poikilotherms are affected by environment:
- explain graph
y= metabolic rate (arbitrary units)
x= body temperature
- exponential increase
- as body temperature goes up so does metabolism
Poikilotherms are affected by environment:
- why is being a poikilotherm a bed adaptation for large organisms?
- poor strategy because the whole body cannot change at the same rate…its easier for a small body with a larger surface:volume ratio
Operative temperature:
- of a snake…describe graph
x= hour of day
y= temperature (C)
- temp variations in about 4/5 degrees
- amphibians can change by about 10
- only active within the operative range (dotted line)
- higher movement is around lunch - 9pm(cold temps (below zero)
- higher activity during 9am-3pm…(temp at about 15C)
- higher activity during 8am-1
- *as temp increases the hour of operation range becomes narrower
Some animals change position to regulate temperature aka
microhabitats
Example of changing microhabitats to regulate temperature ?
- snake
17C its under a tree for shade… - 18C its in the water
- 30C its laying on a rock
- then it shelters itself under a rock (temp brought down to 14)
- goes underground (temp of 16)
**in morning it sits and collects heat…then it begins moving around and getting active…if it gets too hot they stop…hide or lay on a rock so they do not lose a lot of heat /gain too much